I hava an application like
a)A Telnet(Applet)is loaded into my system
b)I type any command like ls or pwd
c)It brings data from webserver
d)I want to know how much time it took to get data,is there any Timer function in winrunner where Timer starts before the command is executed and Timer closes once it gets the data from the webserver
start_transaction and end_transaction functions exist in WinRunner. They can be used on concert with LoadRunner or deployed independently as in this case. Take a look at the help file for exact syntax.